I've never really understood that allure of Hard Rock Cafe's around the world. I recall the T-shirts being kind of popular when i was in high school. I have no idea if they are now. I have only ever been to two of them and last night by demand of a group of people that were visiting, we went there because they wanted to.
As you would expect, the Hard Rock Cafe in Chiang Mai is in the most touristy part of the city and again as you would expect, the restaurant is normally quite busy. What you might not expect, is that it is far more expensive than other restaurants around it and there isn't anything particularly good about their food and drinks.
don't get me wrong, the burger was big, and it was cooked properly, but is it worth $18? I don't think so
If you go to pretty much any Applebees or Chilis this is the kind of food they have. Don't get me wrong - I like those places and when I am in the states I eat at them because I think they are a good value. However, at Hard Rock, the price of food is significantly higher than really anything else in town but doesn't come with any sort of increased quality. Paying 800 Baht for a steak is almost unheard of (this is nearly $30) and if you did accomplish that price it would be something extremely special like Wagyu beef.
They justify this increased price by having a nice interior (which to be fair, is true) and they have memorabilia from famous musicians that I am sure they had to pay a lot for. It's more of a museum that serves average American food.
The cocktails and booze come at an extremely elevated price. Perhaps you aren't aware of this, but paying nearly 400 B ($15) for a fruity drink with some vodka in it (even if it is Grey Goose) is practically unheard of anywhere in Thailand.
When you look at the menu the prices will seem high, but keep in mind that they are actually 17% HIGHER than is listed on the menu, because unlike pretty much every other place, they haven't included tax in the price already and the have mandatory service charge.
Overall, I would say that if you are rich and don't mind paying $50 a person to eat what can only be described as average western food that is easily acquired at dozens of other places for around $15 a person, then go to Hard Rock. I only went because someone else insisted and was paying for it.